Rhodium acetate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 March 1986 – 14 March 1986

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted according to OECD guideline No. 404 and to GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Report date:

1986

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Rhodium(3+) acetate

EC Number:

247-460-0

EC Name:

Rhodium(3+) acetate

Cas Number:

42204-14-8

Molecular formula:

C6H9O6Rh

IUPAC Name:

Rhodium(3+);triacetate

Test material form:

solid: crystalline

Details on test material:

- Name of test material (as cited in study report): rhodium (III) acetat “braun”
- Substance type: brown crystals
- Physical state: solid
- Composition of test material, percentage of components: 39.54% Rh
- Lot/batch No.: 6091
- Stability under test conditions: stable throughout the test period
- Storage condition of test material: at room temperature
- Other: soluble in water

Test animals

Species:

rabbit

Strain:

other: White Russian (albino)

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Asta-Werke AG, D-4800 Bielefeld 14
- Age at study initiation: 4-6 months
- Weight at study initiation: 2.10-2.15 kg
- Housing: individually in ASTA Model stainless steel cages
- Diet (e.g. ad libitum): standard diet, ssniff K “special diet for rabbits” supplied by ssniff Spezialfutter GmbH D-4770 Soest, frequency of feeding not mentioned
- Water: ad libitum
- Acclimation period: 1 day before application of test material

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±1
- Humidity (%): 55±10
- Photoperiod (hrs dark / hrs light): 6 am-6 pm fluorescent tube lighting, 6 pm-6 am “natural light-dark-rhythm”

Test system

Type of coverage:

occlusive

Preparation of test site:

shaved

Vehicle:

water

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g

VEHICLE
- Amount(s) applied (volume or weight with unit): 0.25 ml
- Purity: demineralised

Duration of treatment / exposure:

4 hrs

Observation period:

1, 24, 48 and 72 hrs after removal of the patch

Number of animals:

3 females

Details on study design:

TEST SITE
- Area of exposure: dorsal skin area between shoulder and sacrum
- % coverage: not specified
- Type of wrap if used: The site of application was covered with approx. 6.25 cm2 of a linen cloth which adhered to a synthetic film glue. A bandage (Acrylastic, No. 2408, width 8 cm) was wrapped several times around the trunk to provide a complete occlusion.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no

SCORING SYSTEM: Erythema (and eschar) formation and oedema formation were assessed qualitatively and quantitatively on the skin of 3 rabbits using the Draize method, 1, 24, 48 and 72 hrs after removal of the patch. The cutaneous irritation index at the four time points was determined separately for erythema (and eschar) formation and oedema formation, based on the arithmetical mean values of the individual grades. The irritation index was graded in a modified method according to Gilman et al:

Irritation index Evaluation
0.0-0.5 non-irritant
0.6-3.0 slightly irritant
3.1-5.0 moderately irritant
5.1-8.0 severely irritant

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 1, 24, 48 and 72 hrs

Score:

ca. 0.3

Max. score:

8

Reversibility:

fully reversible within: 48 hrs

Results 2

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 1, 24, 48 and 72 hrs

Score:

ca. 0.25

Max. score:

4

Reversibility:

fully reversible within: 48 hrs

Remarks on result:

other: Very slight erythema (grade 1) was seen at 1 hour after removal of the patches in two of the rabbits and was still evident at 24 hours in one of these animals. Recovery was complete at 48 hrs.

Results 3

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 1, 24, 48 and 72 hrs

Score:

ca. 0

Max. score:

4

Irritant / corrosive response data:

Only very slight erythema (grade 1) was seen in two of the three rabbits and complete recovery occurred within 24 and 48 hrs after removal of the patches. There was no evidence of oedema.

Other effects:

There was no evidence of any systemic toxicity following dermal application.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In a guideline study, to GLP, rhodium (III) acetate “brown” (0.5 g) was applied to the shaved, intact skin of three rabbits (4-hr occluded) and irritant reactions were assessed 1, 24, 48, and 72-hr after patch removal. The test item produced a primary irritation index of 0.3 (very slight but reversible erythema observed in two animals). No eschar formation, oedema, or systemic toxicity was apparent.

Executive summary:

In an OECD Test Guideline 404 study, rhodium (III) acetate “brown” was investigated for irritant (and corrosive) effects following a 4-hr (occluded) application (0.5 g) to the shaved, intact skin of three female White Russian rabbits. The test sites were quantitatively and qualitatively assessed for erythema (and eschar) formation and oedema 1, 24, 48 and 72 hrs after removal of the patches.

 

The overall skin irritation score was 0.3. Very slight erythema (grade 1) was seen in two animals but the findings had completely disappeared 48 hr after removal of the patches. No eschar formation or oedema was seen in any animal and no systemic-toxic effects were apparent.

 

Based on the results of this study, no classification for skin irritation is required according to EU CLP criteria (EC 1272/2008).